Concentration and Membrane Fluidity Dependence of Odor Discrimination in the Turtle Olfactory System

In the present study, we examined the concentration dependenceof odor discrimination in turtle olfactory bulbar responsesusing the cross-adaptation technique. In the odorant pairs withdiverse molecular structures, the degree of discrimination wasunchanged or only slightly decreased with an increase in odorantconcentrations, suggesting that odorants are well discriminatedeven at high concentrations. In the odorant pairs with closelyrelated molecular structures, the degree of discrimination wasdecreased with an increase in odorant concentrations. An increasein the temperature of turtle olfactory epithelium also decreasedthe ability to discriminate these odorants. There was a goodcorrelation between changes in the odor discriminating abilityinduced by an increase in odor concentrations and those inducedby a temperature increase. The liposomes were made of lipidsextracted from the turtle olfactory epithelia and changes oftheir membrane fluidity induced by adsorption of odorants weremonitored with DPH. There was a good correlation between a decreasein odor discriminating ability and the membrane fluidity changesinduced by odorants. We suggest that decreases in odor discriminatingability induced either by an increase in odor concentrationor by a temperature increase are ultimately caused by changesin the membrane fluidity. Chem. Senses 22: 553–563, 1997.     

Normal Lung Quantification in Usual Interstitial Pneumonia Pattern: The Impact of Threshold-based Volumetric CT Analysis for the Staging of Idiopathic Pulmonary Fibrosis

BackgroundAlthough several computer-aided computed tomography (CT) analysis methods have been reported to objectively assess the disease severity and progression of idiopathic pulmonary fibrosis (IPF), it is unclear which method is most practical. A universal severity classification system has not yet been adopted for IPF.ObjectiveThe purpose of this study was to test the correlation between quantitative-CT indices and lung physiology variables and to determine the ability of such indices to predict disease severity in IPF.MethodsA total of 27 IPF patients showing radiological UIP pattern on high-resolution (HR) CT were retrospectively enrolled. Staging of IPF was performed according to two classification systems: the Japanese and GAP (gender, age, and physiology) staging systems. CT images were assessed using a commercially available CT imaging analysis workstation, and the whole-lung mean CT value (MCT), the normally attenuated lung volume as defined from −950 HU to −701 Hounsfield unit (NL), the volume of the whole lung (WL), and the percentage of NL to WL (NL%), were calculated.ResultsCT indices (MCT, WL, and NL) closely correlated with lung physiology variables. Among them, NL strongly correlated with forced vital capacity (FVC) (r = 0.92, P <0.0001). NL% showed a large area under the receiver operating characteristic curve for detecting patients in the moderate or advanced stages of IPF. Multivariable logistic regression analyses showed that NL% is significantly more useful than the percentages of predicted FVC and predicted diffusing capacity of the lungs for carbon monoxide (Japanese stage II/III/IV [odds ratio, 0.73; 95% confidence intervals (CI), 0.48 to 0.92; P < 0.01]; III/IV [odds ratio. 0.80; 95% CI 0.59 to 0.96; P < 0.01]; GAP stage II/III [odds ratio, 0.79; 95% CI, 0.56 to 0.97; P < 0.05]).ConclusionThe measurement of NL% by threshold-based volumetric CT analysis may help improve IPF staging.     

Characterization of Glial Populations in the Aging and Remyelinating Mouse Corpus Callosum

Cells in the white matter of the adult brain have a characteristic distribution pattern in which several cells are contiguously connected to each other, making a linear array (LA) resembling pearls-on-a-string parallel to the axon axis. We have been interested in how this pattern of cell distribution changes during aging and remyelination after demyelination. In the present study, with a multiplex staining method, semi-quantitative analysis of the localization of oligodendrocyte lineage cells (oligodendrocyte progenitors, premyelinating oligodendrocytes, and mature oligodendrocytes), astrocytes, and microglia in 8-week-old (young adult) and 32-week-old (aged) corpus callosum showed that young adult cells still include immature oligodendrocytes and that LAs contain a higher proportion of microglia than isolated cells. In aged mice, premyelinating oligodendrocytes were decreased, but microglia continued to be present in the LAs. These results suggest that the presence of microglia is important for the characteristic cell localization pattern of LAs. In a cuprizone-induced demyelination model, we observed re-formation of LAs after completion of cuprizone treatment, concurrent with remyelination. These re-formed LAs again contained more microglia than the isolated cells. This finding supports the hypothesis that microglia contribute to the formation and maintenance of LAs. In addition, regardless of the distribution of cells (LAs or isolated cells), astrocytes were found to be more abundant than in the normal corpus callosum at 24 weeks after cuprizone treatment when remyelination is completed. This suggests that astrocytes are involved in maintaining the functions of remyelinated white matter.

     

Phenological traits of the mangrove Rhizophora stylosa Griff. at the northern limit of its biogeographical distribution

The vegetative and reproductive phenology of the subtropical mangrove species Rhizophora stylosa was investigated at Manko Wetland, Okinawa Island, Japan. We assessed phenology using litterfall data over four years. Leaf and stipule litterfall occurred throughout the year, with distinct seasonal patterns. Kendall’s coefficient of concordance, W, revealed that the monthly changes in leaf and stipule litterfall were strongly and significantly concordant among years. Leaf litterfall was significantly correlated with monthly maximum wind speed and monthly day length, and stipule litterfall was significantly correlated with monthly mean air temperature and relative humidity. Branch litterfall showed no clear monthly pattern and correlated well with monthly maximum wind speed. Mean total litterfall was 11.2 Mg ha^?1 year^?1, with the largest component being vegetative organs (78.7 %). Flower, fruit, and propagule litterfall were all highest in summer and lowest in winter. The W values revealed that most reproductive organs in litterfall had significant monthly trends. Flower and fruit litterfall were significantly correlated with monthly day length and monthly mean air temperature, respectively. The average development periods from flower buds to flowers, fruits, and mature propagules were approximately 2–3 months, 4–5 months, and 11–12 months, respectively. Except for branches, all vegetative and reproductive components of litterfall had approximately one year cycles.     

Th2 polarization enhanced by oral administration of higher doses of antigen

Although oral administration of a soluble proteinantigen can induce various immune responses, theeffect of the dosage of oral antigen on thepredominance of Th2-type cytokine and antibodyresponses has not been well clarified yet. In thepresent study, we fed T cell receptor (TCR) transgenic(tg) mice various amounts of chicken ovalbumin (0.1,5, and 250 mg) and examined the resulting immuneresponses to this antigen. In these TCR tg mice, theresponses of antigen-specific T cells were greatlyamplified concomitantly with significantantigen-specific cytokine secretion. We found that ahigh dose (250 mg) of antigen significantlyupregulated the serum antigen-specific IgG1 and IgAantibody responses in mice later intraperitoneallyinjected with antigen plus adjuvant. The miceadministered the same oral dose but not immunizedshowed upregulation of Th2-type IL-4 and IL-5secretion and downregulation of Th1-type IL-2 andIFN-. This enhancement of Th2-type cytokineand antibody responses was more marked when largerdoses of antigen orally administered. These resultsdemonstrated that antigen feeding induces thedevelopment of T cells secreting Th2-type cytokines ina dose-dependent manner and that these T cells have ahelper function for the production of antibodies ofthe Th2-type isotypes. This experimental system shouldbe useful to screen foods and other substances thatcan modulate Th2-type responses relating to allergy.     

Breeding of African green monkeys (Cercopithecus aethiops) under indoor individually-caged conditions.

This paper reports the results of reproduction with 45 wild African green monkeys (Cercopithecus aethiops) (36 females and 9 males) during the nine years from 1981 to 1989 under indoor individually-caged conditions. In 206 cases of menstruation observed, menstrual discharge lasted for 2.5 +/- 1.2 days in cycles of 22-48 days, and the length of each menstrual cycle was 31.2 +/- 6.5 days. Females who had regular menstrual cycles were subjected to "one-to-one timed mating"; females and males were put together on a one-to-one basis daily only for a certain period of time on and after the day of ovulation. Females who had irregular menstrual cycles or had no menstruation were subjected to "every-other-day mating"; females and males were put together on a one-to-one basis every other day for at least 16 weeks. The pregnancy rate (No. of pregnant females/No. of mated females) by one-to-one timed mating was 48.9% (116/237); 2.0 mating trials were needed to obtain one case of pregnancy. On the other hand, the pregnancy rate (No. of pregnant females/No. of mating trials) by every-other-day mating was 96% (48/50). Females who delivered normally totaled 129. The mean gestation period was 165 days when males, weighing 343 g on average at birth, were delivered, and 166 days when females, weighing 318 g on average at birth, were delivered. The male and female newborns were nursed for 131 and 138 days, respectively, on average. Details are summarized in Table 3. This paper also reports 23 cases of abortion, 6 stillbirths, and 6 cases of Caesarean section, by which three live fetuses and three dead fetuses were obtained.     

Protein requirement of the prawn Marsupenaeus japonicus estimated by a factorial method

The protein requirement to give maximum body protein retention in the prawn Marsupenaeus japonicus was assessed by determining both daily protein needed for maintenance (M) and daily body protein increment (G) when the juvenile prawn was maintained on a diet containing high quality protein. The body protein increment was obtained by determining carcass nitrogen increment when the prawn was fed on casein-based diets. The protein required for maintenance was estimated by regressing weight gains of the prawn on the diets containing graded levels of casein. True daily increase or retention of body protein in the prawn corresponded to the sum of G and M, and it was 3.2 g protein per kg body weight per day. The dietary protein requirement of juvenile M. japonicus for maximum body protein retention was suggested to be about 10 g per kg body weight per day providing that the prawn was fed the casein-based diet containing 50% crude protein (net protein utilization = 32) at the feeding level of 2%.     

Syntheses of Unsaturated Lactones

6-Pentyl-α-pyrone, 6-propyl-α-pyrone and 4-decenoic acid-δ-lactone were prepared, and the nature of their flavors was investigated. Unsaturated lactones having the best flavorous nature as a butter or butter cake flavor among the lactones having double bond at various site, were 2-ene-δ-lactones which have a double bond at the α-position of the lactone ring and α-pyrones which have two double bonds at the α- and γ-positions. The flavor of 4-deceno-δ-lactone which has a double bond at the γ-position was the worst of them.     

Synthesis of novel triplet drugs with 1,3,5-trioxazatriquinane skeletons and their pharmacologies. 1: Synthesis of triplet drugs with morphinan skeletons

We synthesized symmetrical and nonsymmetrical triplet drugs with 1,3,5-trioxazatriquinane skeletons. The isolation of key intermediates, oxazoline dimers, made it possible to effectively produce nonsymmetrical triplets. Among the synthesized triplets, KNT-93, composed of three identical opioid μ receptor agonists, showed dose-dependent antinociception via the μ receptor. The effect was 56-fold more potent than that of morphine, a representative μ agonist. The profound analgesic effect induced by KNT-93 might result from simultaneous occupation of three μ opioid receptors.